There is increasing evidence that those who experience changes in their life routine have a tendency to become physically ill. A large literature has reported attempts to achieve ratio type measurement of life changes by the use of psychophysical measuring techniques. Other research using the resulting measures has shown that those scoring high in "life change units" are likely to become physically ill. We are hoping to extend research in this area on several fronts. It is vital, we maintain, to study the cultural variation in the perceptions of the stressfulness of life changes and illness, particularly psychological impairment. Further, the cultural effects upon the linkages between life changes and illness need to be explored. We will have our data relevant to these questions gathered and ready for analysis by the beginning of the proposed renewal period. We will have conducted a "ranking" survey of random sample of El Paso adult (ages 21-60) Mexican-Americans and Anglow and a cluster sample of Mexican adults (ages 21-60) living in Ciudad Juarez. We will also have conducted a set of two "incidence" surveys six months apart on a panel of respondents representing the same populations. We propose, then, with this renewal grant to analyze the data to determine what differences between and among ethnically homogeneous groups might exist in their perception of the relative degree of stress associated with various life changes and in the effect of stress upon illness. In addition, we will be able to analyze the value of ratio-measurement in terms of its comparative predictive power, its use in taking into account subcultural variations and in terms of its validity as a measurement tool. The information discovered during the course of this research would, on the scholarly level, constitute an important contribution to the developing literature on the etiology of psychological impairment. On the applied level the information will be of obvious use to physical and mental health workers concerned with health.